Internet Protocol (IP) transmission is the most prevalent transmission technology nowadays, and full-IP communication networks are a megatrend. In radio communication, Asynchronous Transfer Mode (ATM) is still the most widely applied. However, Wideband Code Division Multiple Access (WCDMA), Global System for Mobile communications (GSM), Worldwide Interoperability for Microwave Access (WiMAX), and Long Term Evolution (LTE) systems in the radio communication field begin to support IP transmission in order to meet network development requirements. The old ATM transmission mode is evolving toward IP transmission. For example, a WCDMA R6 system and later versions of WCDMA support an IP bearer as a signaling transmission bearer of an IUB interface.
Regardless of transmission modes, a signaling path is the most essential path of a Base Station System (BSS) in the transmission process. If the signaling path is interrupted, the service of the entire BSS will be interrupted. In order to increase reliability of a base station, if the current signaling path fails, the service needs to hand over to another signaling channel seamlessly without interrupting the upper-layer service.
During evolution from ATM transmission to IP transmission, the ATM transmission coexists with the IP transmission. In the prior art, the solution to protecting signaling transmission is always a redundancy protection solution based on a homogeneous physical link. That is, the signaling path protection solution is specific to only IP transmission, ATM transmission, or another transmission mode, without being compatible with different transmission modes.
For example, the signaling path protection solution is based on an 1.630 ATM Protection Switching technology, Multi-service Packet Switching (MPS) technology specific to STM-1, or Trunking technology specific to Ethernet.
The prior art has the following disadvantages. The protection for signaling transmission is always based on a link layer or physical layer, and links that involve reciprocal switching are based on the same transmission protocol. One situation exists, i.e., different terminals may need to be connected through intermediate network devices. In this situation, the transmission protocols between intermediate network devices and the transmission protocols between an intermediate network device and a terminal are diversified, it may be impossible to perform end-to-end protection switching in the prior art.